The present invention relates to plate-type heat exchangers of the kind comprising a plurality of rectangular plates whose transverse dimension is the width of the exchanger and whose maximum longitudinal dimension is the length of the exchanger, said plates being stacked and joined together with sealed mutual spacings along the thickness of the exchanger to form at least:
(a) a plurality of first passages for the cooling of a refrigerating mixture, PA0 (b) a plurality of second passages for the cooling of a gas which is to be processed, said first and second passages having inlets at a first longitudinal extremity of the exchanger and outlets at least close to a second longitudinal extremity of the exchanger; PA0 (c) a plurality of third passages for the heating of the refrigerating mixture, having inlets which are at least close to said second extremity of the exchanger and having outlets which are laterally arranged at a distance from said first exchanger extremity, and PA0 (d) a plurality of fourth passages situated in longitudinal extensions left free by said third passages, extending longitudinally from the outlet extremity of said third passages to said first extremity of the exchanger, the inlets and outlets of said fourth passages being arranged laterally with respect to the exchanger.
Hereinafter such heat exchangers will be referred to as "of the kind described".
It is an object of the invention to provide structural forms which are appropriate more particularly for an arrangement of the exchanger in accordance with which its greater dimension is situated vertically.